Do not overwrite the disk signature, if we install the boot code into the mbr.

Modified: trunk/reactos/subsys/system/usetup/bootsup.c
Modified: trunk/reactos/subsys/system/usetup/usetup.h

--- trunk/reactos/subsys/system/usetup/bootsup.c	2005-09-17 21:22:47 UTC (rev 17902)
+++ trunk/reactos/subsys/system/usetup/bootsup.c	2005-09-17 22:00:35 UTC (rev 17903)
@@ -1002,13 +1002,13 @@

   UNICODE_STRING Name;
   HANDLE FileHandle;
   NTSTATUS Status;

-  PUCHAR OrigBootSector;
-  PUCHAR NewBootSector;

+  PPARTITION_SECTOR OrigBootSector;
+  PPARTITION_SECTOR NewBootSector;

 
   /* Allocate buffer for original bootsector */

-  OrigBootSector = (PUCHAR)RtlAllocateHeap(ProcessHeap,
-					   0,
-					   SECTORSIZE);

+  OrigBootSector = (PPARTITION_SECTOR)RtlAllocateHeap(ProcessHeap,
+				                      0,
+                                                      sizeof(PARTITION_SECTOR));

   if (OrigBootSector == NULL)
     return(STATUS_INSUFFICIENT_RESOURCES);
 
@@ -1052,9 +1052,9 @@

 
 
   /* Allocate buffer for new bootsector */

-  NewBootSector = (PUCHAR)RtlAllocateHeap(ProcessHeap,
-					  0,
-					  SECTORSIZE);

+  NewBootSector = (PPARTITION_SECTOR)RtlAllocateHeap(ProcessHeap,
+					             0,
+                                                     sizeof(PARTITION_SECTOR));

   if (NewBootSector == NULL)
   {
     RtlFreeHeap(ProcessHeap, 0, OrigBootSector);
@@ -1090,7 +1090,7 @@

 		      NULL,
 		      &IoStatusBlock,
 		      NewBootSector,

-		      SECTORSIZE,

+		      sizeof(PARTITION_SECTOR),

 		      NULL,
 		      NULL);
   NtClose(FileHandle);
@@ -1102,9 +1102,9 @@

   }
 
   /* Copy partition table from old MBR to new */

-  RtlCopyMemory ((NewBootSector + 446),
-		 (OrigBootSector + 446),
-		 4*16 /* Length of partition table */);

+  RtlCopyMemory (&NewBootSector->Signature,
+		 &OrigBootSector->Signature,
+		 sizeof(PARTITION_SECTOR) - offsetof(PARTITION_SECTOR, Signature) /* Length of partition table */);

 
   /* Free the original boot sector */
   RtlFreeHeap(ProcessHeap, 0, OrigBootSector);

--- trunk/reactos/subsys/system/usetup/usetup.h	2005-09-17 21:22:47 UTC (rev 17902)
+++ trunk/reactos/subsys/system/usetup/usetup.h	2005-09-17 22:00:35 UTC (rev 17903)
@@ -30,6 +30,7 @@

 /* C Headers */
 #include <ctype.h>
 #include <stdio.h>

+#include <stddef.h>

 
 /* PSDK/NDK */
 #include <windows.h>